$\bf{
242 {}^{+14}_{-15}}$
|
OUR AVERAGE
|
$245.2$ $\pm13.1$ ${}^{+4.6}_{-9.6}$ |
|
|
1 |
|
BES3 |
$192$ ${}^{+20}_{-17}$ ${}^{+62}_{-43}$ |
|
|
|
|
BES3 |
• • • We do not use the following data for averages, fits, limits, etc. • • • |
$175$ $\pm57$ $\pm25$ |
|
|
2 |
|
BES3 |
$273.5$ $\pm21.4$ ${}^{+6.1}_{-64.0}$ |
|
|
3 |
|
BES3 |
$83$ $\pm14$ $\pm11$ |
|
0.6k |
|
|
BES3 |
$\text{< 76}$ |
90 |
|
4 |
|
BES3 |
$190$ $\pm9$ ${}^{+38}_{-36}$ |
|
4265 |
5 |
|
BES3 |
$57$ $\pm12$ ${}^{+19}_{-4}$ |
|
|
6 |
|
BES3 |
$0$ ${}^{+44}_{-0}$ |
|
231 |
7, 8 |
|
CLEO |
$67.7$ $\pm20.3$ $\pm7.7$ |
|
264 |
|
|
BES2 |
$\text{< 153}$ |
90 |
|
9, 8 |
|
BES2 |
$\text{< 30}$ |
|
|
8 |
|
BES2 |
1
From a fit of the measured ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \eta}^{\,'}}$ lineshape that accounts for the abrupt distortion observed at the ${{\mathit p}}{{\overline{\mathit p}}}$ threshold through interference with a second previously unseen narrow resonance near 1870 MeV. The fit uses Breit-Wigner functions for the signal shapes and includes known backgrounds and contributors.
|
2
From a fit to ${{\mathit \gamma}}{{\mathit \phi}}$ invariant mass. Angular analysis consistent with $\mathit J{}^{PC} = 0{}^{-+}$. Other $\mathit J{}^{PC}$ not excluded.
|
3
Pole width from a fit of the measured ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \eta}^{\,'}}$ lineshape to a Flatte formula that accounts for the abrupt distortion observed at the ${{\mathit p}}{{\overline{\mathit p}}}$ threshold; the fit also includes known backgrounds and contributors, as well as an $\mathit ad~hoc$ Breit-Wigner function (M $\approx{}$ 1919 MeV; $\Gamma $ $\approx{}$ 51 MeV) that is required for a good fit.
|
4
From the fit including final state interaction effects in isospin 0 ${\mathit S}{\mathrm -wave}$ according to SIBIRTSEV 2005A. Supersedes ABLIKIM 2010G.
|
5
From a fit of the ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \eta}^{\,'}}$ mass distribution to a combination of ${{\mathit \gamma}}{{\mathit f}_{{1}}{(1510)}}$ , ${{\mathit \gamma}}{{\mathit X}{(1835)}}$ , and two unconfirmed states ${{\mathit \gamma}}{{\mathit X}{(2120)}}$ , and ${{\mathit \gamma}}{{\mathit X}{(2370)}}$ , for ${{\mathit M}}$( ${{\mathit p}}{{\overline{\mathit p}}}$ ) $<$ 2.8 GeV, and accounting for backgrounds from non-${{\mathit \eta}^{\,'}}$ events and ${{\mathit J / \psi}}$ $\rightarrow$ ${{\mathit \pi}^{0}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \eta}^{\,'}}$ .
|
6
The selected process is ${{\mathit J / \psi}}$ $\rightarrow$ ${{\mathit \omega}}{{\mathit a}_{{0}}{(980)}}{{\mathit \pi}}$ . This state may be due also to ${{\mathit \eta}_{{2}}{(1870)}}$ or to a combination of ${{\mathit X}{(1835)}}$ and ${{\mathit \eta}_{{2}}{(1870)}}$.
|
7
From a fit of the ${{\mathit p}}{{\overline{\mathit p}}}$ mass distribution to a combination of ${{\mathit \gamma}}{{\mathit X}{(1835)}}$ , ${{\mathit \gamma}}{{\mathit R}}$ with ${{\mathit M}}({{\mathit R}}$) = 2100 MeV and ${{\mathit \Gamma}}({{\mathit R}}$) = 160 MeV, and ${{\mathit \gamma}}{{\mathit p}}{{\overline{\mathit p}}}$ phase space, for ${{\mathit M}}$( ${{\mathit p}}{{\overline{\mathit p}}}$ ) $<$ 2.85 GeV.
|
8
Evidence for a threshold enhancement in the ${{\mathit p}}{{\overline{\mathit p}}}$ mass spectrum was also reported by ABE 2002K, AUBERT,B 2005L, and WANG 2005A in ${{\mathit B}^{+}}$ $\rightarrow$ ${{\mathit p}}{{\overline{\mathit p}}}{{\mathit K}^{+}}$ , WANG 2005A in ${{\mathit B}^{0}}$ $\rightarrow$ ${{\mathit p}}{{\overline{\mathit p}}}{{\mathit K}_S^0}$ , ABE 2002W in ${{\overline{\mathit B}}^{0}}$ $\rightarrow$ ${{\mathit p}}{{\overline{\mathit p}}}{{\mathit D}^{0}}$ , DEL-AMO-SANCHEZ 2012 in ${{\mathit B}}$ $\rightarrow$ ${{\mathit D}}$ (${{\mathit D}^{*}}$) ${{\mathit p}}{{\overline{\mathit p}}}$ (${{\mathit \pi}}$), and WEI 2008 in ${{\mathit B}^{+}}$ $\rightarrow$ ${{\mathit p}}{{\overline{\mathit p}}}{{\mathit \pi}^{+}}$ decays. Not seen by ATHAR 2006 in ${{\mathit \Upsilon}{(1S)}}$ $\rightarrow$ ${{\mathit p}}{{\overline{\mathit p}}}{{\mathit \gamma}}$ .
|
9
From the fit including final state interaction effects in isospin 0 ${\mathit S}{\mathrm -wave}$ according to SIBIRTSEV 2005A. Systematic errors not estimated.
|